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Catadioptric Telescope

The Catadioptric telescope is a hybrid telescope which combines shaped mirrors and lenses in designs that have all spherical surfaces that are much easier to manufacture.

These scopes have an overall greater degree of error correction than their all lens or all mirror counterparts.

They have a wide field of view and take advantage of a folded optical path, or a combination of any or all of these attributes.

Many catadioptric scope types such as the Schmidt-Cassegrain and Maksutov-Cassegrain employ “correctors”, a lens or curved mirror in a combined image-forming optical system so that the reflective or refractive element can correct the aberrations produced by its counterpart.

While there are numerous variations, they can be divided into two primary designs: compact and non-compact. In the compact design, the corrector plate is located at or near the focus of the primary mirror.

In the non-compact, the corrector plate remains at or near the center of curvature of the primary mirror.

They are an excellent all round telescope, easy to use, extremely portable and are good for deep sky and planetary viewing.

Schmidt Cassegrain TelescopeTheir compact design makes them extremely portable for a given aperture. A high f-ratio means they are good for narrow field, deep sky and planetary viewing.